No Music Showing on iPod = Real Tears

I come to you yet again begging for assistance as it seems all of my electronics are suicidal this month and is causing me some real emotional turmoil.

Here's the low-down:

I plugged my 120gb classic iPod (about 2 years old, no idea what generation that makes it, I've lost count!) last night to add some new songs, turned off my computer and unplugged my iPod after it gave me permission, same as always. Assuming everything was happy and normal I went to bed and woke up this morning to find that my iPod is showing 0 music on it at all. The odd thing is, the music is still obviously on there somewhere because it's showing that I only have 49.4gb available on the pod.

I plugged it in when I got home from work today to my Mac that it is synced to, having read online that if you reconnect it to itunes, the music will likely show up again, but had no such luck.

The first time I connected it, everything was fine, but now I'm getting a popup saying "Mac OS X can't repair the disk "Kristin's iPod". You can still open or copy files on the disk. Back up the disk and reformat it as soon as you can."

I've tried using a Pod to Mac program to at least get the music off of the iPod so I could reformat it then just put the music back on, but the music is now showing up as "other" when plugged in so it's completely useless.

It's also not reading on my PC and I'm at a loss of what to do as I don't have 90% of the music on my pod backed up due to a recently (and highly tramuatizing) broken external hard drive.

Any insight would be greatly appreciated as as cliche as it sounds, music is my life, and without it the subway rides to work will surely become a new kind of he.ll.